Why we built it
I was spending too much time trying to work this out myself. Not in a fun spreadsheet way, but in the annoying, repetitive way: checking whether a supermarket counted as groceries, whether a wallet payment was excluded, whether points were actually worth anything, and whether a promotion I remembered was still live.
Banks publish the details in different formats, update them at different times, and often put the useful bit several clicks away from the headline offer.